Method and apparatus for the production of filaments



June 24, 1958 H. WEBER ETAL 2,839,784

METBOD AND APPARATUS FOR THE PRODUCTION OF FILAMEI ITS Filed March 26,1953 2 Sheets-Shee t 1 FIGJ.

I I INVENTORS. 34a HAROLD WEBER 26a WALTER D. PAIST Y M114 4 TTORNEYS.

June 24, 1958 WEBER ET AL METHOD AND APPARATUS FOR THE PRODUCTION OFFILAMENTS Filed March 26, 1953 2 Sheets-Sheet 2 I NVENTORS. HAROLDWEBERWALTER D. PAIST Q 2,839,784 ICC Patented J n 24,1

METHOD AND APPARATUS FOR THE PRODUCTION OF FILAMENTS Application March26, 1953, Serial No. 344,738

17 Claims. (Cl. 18-8) This invention relates to the production offilamentary materials and relates more particularly to the production ofa-rtificialfilaments from comminuted fusible filament-forming materials.

' One method heretofore employed for the production of artificialfilaments from comminuted filament-forming material involved urging thematerial in powdered form, ,by means of a tamper, against one side of aheated plate having spinning orifices therein so that the powderedmaterial is fused by heat supplied from said plate, supplying freshpowdered material to the plate, and drawing away the fused materialthrough said orifices inthe form of filaments. Although satisfactoryfilaments have been spun in this manner the uniformity of the filamentshas not been as high as desired.

1 It is an object of this invention to provide anovel apparatus andprocess for the production of artificial filaments from comminutedfusible filament-forming materials. e

Afurther object of this invention is the provision of a new and improvedapparatus and process of this character for producing filaments ofgreater uniformity,

than is obtainable with the apparatus and process of the prior art.Other objects of this invention will appear fromthe followingdescription and claims.

According to this invention particles of fusible filament-formingmaterial are forced through the orifices of a heated spinning jet by aplurality of rams having working faces'acting against said jet. The ramsapply a continuous mechanical pressure to the particles on one side of alayer of'the material in contact with the jet so as to urge saidparticles towards said jet, whereby the particles are fused by heatsupplied from the jet, and the fused material is continuously drawnthrough the orifices of the jet in the form of filaments. Thismechanical pressure, although applied continuously to said layer'ofmaterial, is applied intermittently to difierent areas of said layer,and fresh particles of material are supplied to said areas during theperiods of time between successive applications of the mechanicalpressure thereto.

More particularly, the spinning jet is in the form of a long,electrically heated plate having a plurality of spinning orifices and issituated immediately below a long slit at the bottom of a chamber.Powdered filamentof elongated rams, each having onefiat side and eachhaving a working face extending substantially the entire length of theslit, the rams being arranged between guides forming material is urgedagainst this plate by a pair in the chamber with the flat sides of therams in close ram, after which the first ram is raised and then moveddown to apply a tamping force to said layer while the second ram isstill being pressed forcibly against said layer. This sequence ofoperations is repeated several times per second. The powdered materialin contact with the jet plate is fused by the heat supplied by saidplate and is drawn off through the orifices of said plate, while theupper particles of the layer, of material adjacent to the plate, i. e.the particles in contact with said rams, remain unfused until they areforced closer to the plate by repeated downward movements of the ramsagainst fresh powdered material which is intermittently supplied to thetop of said layer. Thus, when a ram is raised a small quantity of freshpowdered material fiows, by gravity, under said ram to make up for themolten material force through the jet plate by said ram during itsdownward stroke.

The drawing away of the fused material passing through the jet plate maybe effected by simply allowing the products emerging from the orificesin the heated plate to fall away by their own weight. Except intheproduction of bristles and like heavy filament-ary products, however, itis desirable to draw the fused material away at a greater linear rate,as by passing the filaments around a draw-roller driven at theappropriate peripheral speed and disposed atia suificient distance fromthe heated plate for the filaments to harden by cooling. I e

The filamentary'products made in accordancewith the invention can thusbe in the form of a bundle of fine filaments, e. g. of 10 denier down to1 denier or less, associated together to form a thread which can betwisted to any desired degree or, alone or in association with othersuch threads, can be converted into staple fibers for use in staplefiber yarns. Alternatively, however, filaments of heavy denier (e. g. of10-200 denier) can be made, suitable for employment'singly or in smallgroups in the manner of yarns for textile'purposes. ,By the use of asingle orifice in the plate, still heavier filaments of up to 4000denier or more can be produced for such purposes as bristles. Again, byproviding an orifice in the plate in the form of a slit, narrow bands]or ribbons, or strawlike products can be made, of a width of the orderof 1 to 5 mm. or more. '1 Such products The degree of draw-down employedfor the production offine filaments, i. e. the ratio between the area ofcross-section of the orifices in the .plate and the area ofcross-section of the filaments, is preferablyof the order of 500 to 1000or more. For heavy filaments, however, a lowerdegree of draw-down can beemployed, ranging from unity upwards according to the denier of theproducts required. The possibility of using a high degree of draw-downmakes it unnecessaryto use very fine orifices in the plate, and; enablesthe same orifices to be used for filaments of verydifie-rent deniers.Thus, orifices of the order of '0.0 2"or more in diameter, which offerno special difficulty in production, can be used, and the denier of theresulting filaments determined by the degree of draw-down, However, theproperties of the filaments vary with the degree of draw-down; forexample, when a lower degree of draw-down is employed the resultingfilaments may exhibit a higher elongation at break. 3 e I I I,

From the draw roller by which the draw-down is effected, the filamentsproceed to .-a collecting device,

e. g. to a simple reel or, in the case of a bundle of filaments to beformed into acontinuous filamentyarn, to acentrifugal pot or othertwisting and winding device. on their w f m. he hea e P a t he. allsq s9- yice, the filaments may be treated with an antistatic lubricant orother finish. The method and apparatus described above can besuccessfully operated in air at atmospheric pressure. tain advantagescan be obtained, however, by maintaining an atmosphere of" an inert gas(e. g. of nitrogen) about the powdered material that has been suppliedto the plate, particularly as regards the range of temperatures to whichthe plate may be heated without damage to resulting filaments bycharring, excessive bubble formation or other defects. For this purposethe vessel into which the powdered material is fed for delivery to theheated plate may be provided with a closure and with a supply pipe forfeeding the inert gas. his not desirable, in general, to'jmaintain thepowdered material supplied under a superatmospheric gaseous pressure,whether of air or of inert gas, since it has been found that the use ofsuch pressure greatly increases a tendency toward the formation ofnumerous small bubbles of gas in the resulting filaments, giving them anopaque appearance and a much reduced specific gravity. Insofar, however,as filamentary products of this charcter may be desirable for certainpurposes, e. g. for thermal or electrical insulation, the use ofpressure affords a convenient means of obtaining them.

Certain other advantages may be obtained by maintaining asub-atmospheric pressure about the powdered material that has beensupplied to the heated plate, particularly as regards the range oftemperatures to which the plate may be heated without damage due tocharring or other decomposition of the material, and as rega'rds therange of properties obtainable in the resulting filaments; Thus, whenthe powdered material'is cellu lose acetate and sub-atmospheric pressureis employed, the temperature may range upwards from the lowesttemperature at which the production of satisfactory filaments ispossible to a temperature which is higher by 80 to Cer 100 C. The use ofhigher temperatures increases the rate (in weight per unit time) atwhich the filaments are produced and the ease with which they can bedrawn away from the orifices in the heated plate. Also, the availabilityof a wide range of practicable temperatures enables'filaments of widelydifferent characters to be obtained, from filaments of high tenacity andrelatively low extensibility produced at low temperatures, to filamentsof lower tenacity but'greater extensibility produced at highertemperatures. Moreover, the use of sub-atmospheric pressure this wayenables a still wider range of materials to be spun into filaments fromthe molten condition. If desired, an inert gas at sub-atmosphericpressure may be used.

By the use of this invention substantially uniform filamentary productscan be produced successfully from a number of fusible filament-formingsubstances, including not only substances which are stable at and abovetheir melting points, but also many which are liable to slowdecomposition and discoloration if maintained for a substantial periodat about the temperature at which they first become'flowable. The methodof the present invention does not require the material to hem a flowablestate for more than a very short period of time. The time during whichthe filament-forming material is being urged towards the jet face, inthe form of apparatus described above, is of the order of 1 minute orless, and the material is subjected to a temperature approaching that ofthe heated jet plate for only a fraction of that time. The very shortperiod of heating enables melt spinning of materials of the typementioned above to be ing point at normal pressure of the mixture.

7 Z ability over a range of temperatures. When using materials withsharp melting points it is often preferable to employ a substantialdegree of draw-down. The materials which have not a sharp melting point,however, can in general be spun quite readily without substantialdraw-down (i. c. with no more than that caused by the weight of theextruded product) to form heavy bristles. As has already been mentioned,cellulose acetate is an example of the materials to which the inventioncan be applied. The cellulose acetate used may be a fully acetylated orpartially deacetylated (e. g. acetone-soluble) product. Although, aspointed out above, the material is subjected to a high temperature foronly a very short time, it is desirable to take reasonable steps tostabilize the material against heat-decomposition. Accordingly, whenusing a partially deacetylated cellulose acetate, it is preferred to usea hot-ripened material, i. e. one deacetylated by ripening at atemperature substantially above room temperature, preferably afterneutralizing part or all of the sulphuric acid employed as a catalyst inthe acetylation process. Further, the cellulose acetate used ispreferably one which, after ripening, has been stabilized by heatingunder pressure with Water or very dilute acid to a temperaturesubstantially above the boil- A further measure, which is applicable toa'number of different materials and which makes easier the production offilarnentary products in accordance with the invention, is to heat theair-dry powdered material in the air or in vacuum, e. g. in the case ofcellulose acetate to a temperature of to 200 C. for a period of /2 tohour. The cellulose acetate may be employed with or without a content ofplasticizer such as triphenyl phosphate or dimethoxy ethyl phthalate.Suitable stabilizers for' the cellulose acetate such as epoxy resins,metal salts, phenolic compounds, etc., may be used.

The materials employed are supplied for the purpose of the invention inpowder form. The fineness of the powder is not critical so long as it isnot too coarse to pass into the layer of material in contact with theheated plate, nor so fine as to clog the apparatus or to give rise todifficulties in handling through blowing about or being drawn awaythrough the vacuum pipe, which is used to place the particles undersub-atmospheric pressure. It has been found satisfactory to use apowder, the particle diameters of which are of about the same order asthe diameter of the spinning orifices in the heated plate. Thus, withorifices of a diameter of 0.025 inch it has been found practicable touse a powder which will pass through'a gauze having 30 openings perlineal inch but is retained by one having 60 openings per lineal inch.

It has been found that the rate at which the material may be caused toflow through the fine orifices in the plate may be greatly increased bycountersinking these orifices, so that the material flowing over theheated plate passes over an inwardly tapered upper portion of theorifice and then, for a very short distance, through the minimumdiameter of said orifice. Thus, a plate having a thickness of .030 inchmay be provided with orifices having a diameter of .004 to .010 inch theorifices being countersunk at an inclusive angle of 50 to 55 so that theactual length of the narrowest portion of the orifice is only .005 inch.

Materials other than cellulose acetate from which filaments' may beproduced according to the present invention include other celluloseesters such as cellulose propionate, cellulose :acetate-pr'opionate andcellulose acetatebutyrate; .cellulose' ethers, such as 'ethyl celluloseand benzyl cellulose; addition polymers such as polyethylene andpolystyrene; other polymers, such as polyhexamethylene-hept'amethyleneurea obtained from hexamethylene diisocyanate andheptamethylene'diamine, 4,4-polyurethane from tetr-amethylene diamineand 1,4-butanediol bis- (chloroformate) polyhexamethylene adipamide,pol-y '2'2 of Fig. l, and

aminocaproic acid and other polyamides, polyethylene glycolterephthalate and other polyesters, and polyaminotri-azoles, such asthose from sebacic dihydrazide and hydrazine.

The powdered form in which the materials are supplied makes it possibleto use mixtures of different materials by mixing together the separatelypowdered materials or to use mixtures of the powdered filament-formingmaterials with other material, such as powdered pigments. Thus, amixture of 95% acetone-soluble cellulose acetate with 5% of thepolyaminotriazole mentioned, and a mixture of 50% of cellulose acetatewith 50% of 66 nylon, and a mixture of 90% of cellulose acetate and ofcellulose propionate of propionyl value 63.4 have been successfullyformed into bristles and drawn down into fine filaments. Further,filamentary products exhibiting colored or other desirable effects canbe produced by mixing with the powdered or granular filament-formingmaterial powdered or granular dyestuffs, or white or colored pigments,or other effect materials, the added materials being incorporated in thefilamentary products as a consequence of the process of theirproduction.

A preferred embodiment of this invention is shown'in the accompanyingdrawing wherein Fig. l is a front elevational view, with parts brokenaway, of the apparatus of this invention,

Fig; 2 is a cross-sectional view taken along the line Fig. 3 is a detailview, in perspective, of the rams used in theiapparatus of thisinvention. I Referring now to the drawing, reference numeral 10designates a spinning'apparatusof this invention having a machine frame11 carrying a hopper 12, said frame being mounted, by any suitablemeans, such as' bolts 13 passing through brackets 14, on a channel ironsupport 16. Comr'ninuted thermoplastic material is placed in the hopper12 6 bars. The bars 31, 31a are connected to means for reciprocating thesame, to be described below, by posts 37, 37a welded, brazed or solderedto saidbars intermediate the ends thereof. The posts 37, 37a comprisecylindrical heads 38, 38a, stems 39, 39a, and nipples 41, 41a adapted tobe received in semicircular grooves or holes 42, 42 a in the bars 31,31a, said grooves being so located that when said bars are mountedbetween the guides 36 all of the posts 37, 3721 are in the same plane.To enable the'bar's 31, 31a to be reciprocated without interfering witheach other a portion of each bar is cut out at 43, 43a, opposite thepoints where the posts are attached to the other bar. The bars 31, 31aare beveled as shown at 44, 44a, 45 and 45a to permit the comminutedmaterial to move more free ly around the rams and towards the jet plate24, the nipples-41, 41a being beveled in a similar manner.

The posts 37, 37a are operatively connected to a drive shaft 46,situated at the top of the machine frame 11, by means of eccentrics 47,47a, pins 48, couplings 49, connecting rods 51, lost motion connections52, tie rods 53 and collars '54. More specifically, the stems 39, 39a ofthe posts are mounted in sleeves 56 (Fig. 2) of packing nuts 61. Thepositions of the collars 54 relative to the and passes down, 'bygravity, into an elongated tamping chamber 17 supported by saidhopperand'communicating, at its upper centralportion '18, with the lowerportion 19 of said hopper. "The thermoplastic material passes throughthe tapered lower'portion of the chamber 17 and is forced out ofa longslit-like'opening 22 (Fig. 2) at the bottom of said chamber andthroughthe orifices '23 of. a heated jet plate 24by the reciprocating action ofI alternately operating tampers or rams 26 and'26a, which are locatedwithin the chamber 17 and extend for substantially the'entire lengththereof. The jet'plate 24 also extends'for substantially the entirelength of the chamber 17 and is'mounted between a cover strip 27 and asupporting .strip .28, both made of electrical 'insulatingmaterial', the

' material forced against said plate by the action of the rams Thereciprocating action of the rams 26,2611 also serves to distribute .thethermoplastiematerial, which enters at the central portion of thechamber. 17, throughout the length of said chamber so that the materialis forced throughthe orifices of the plate 24'along theentire length ofsaid plate.

The rams comprise long bars 31, 31d (Fig.3) having working faces 32,32a,flat sides 33, 33a, and thickened upper portions 34,341 The bars 31,31a are adapted to be mounted so that their working faces 32, 33a may bereciprocated toward and'awjay from the jet plate-24 with the fiat sides33, 33a in sliding contact witheach.-' To maintain the bars 31, 31a inthe Tdesiredr'elationship there are provided guides 36 which engage theouter surfaces of the uppenportions 34, 34a adjacent to the ends'of saidtie rods 53 may be variedby loosening the lock nuts 61 and rotating saidcollars, such rotation of the collars54 being permitted by theconnections between said collars and the heads 38, 38a of the posts 37,37a. The assembly of tie rods 53, collars 54 and rams 26, 26a is urgeddownwards by means of strong compression springs 62,'whose lower endsabut'againstflanges 63 on said tie rods and whose upper ends abutagainst adjustable nuts 64'mounted on threaded sleeves 66, which arefixed in any suitable the frame 11. a

'The lost-motion connections'52 comprise pins 69 carried by the tie rods53 and fitting in slots 71 in the enlarged ends of the connecting rods51, the latter being slida'bly mounted within bearings 72 in the sleeves66. By virtue of these lost motion connections the upward movement ofthe connecting rods 51 lifts the tie rods 53 and the rams 26, 26aagainst the action of the springs 62 while the downward motion of saidconnecting rods permits the springs to actuate the rams downwardly toperform their t'amping action. Thus, the working face 32-, 32a ofeachram 26, 26a is raised to substantially th'e'same predeterminedposition upon each revolution of the shaft 46. This position isadjustable relative to the jet plate 24 by means of'th-e threadedconnections between connecting rods 51 and couplings &9 and also bymeans of the threaded connections between'the collars 54 and the tierods 53. Normally, the position to which the working faces of the ramsare lifted is about 7 in. above the upper surface ofthe plate 24. Therams 26, 26a descend, however, only so far as the thickness of the layerof material lying over the jet plate will permit, the lostmotionconnections 52 allowing the residual movement of the connecting rods5'1, under the influence of the eccentrics 47, 47a, to take placeindependently of the tamper rods and tampers. The lowest possibleposition of the tie rods 53 and working faces 32, 32a is determined bythe adjustment of the collars 54 which act as stops engaging the uppersurfaces of the packing glands One pair of eccentrics 47 is mounted onthe shaft 46 at a position removed from the other pair'of eccentrics47a, so that when both of the eccentrics 47 are in their highestposition both of the other eccentrics 47a are in their lowest position.Accordingly, when the ram 26 is raised to'its highest position, theother farm 26a is being pressed, under the action of the springs 62,against the comminut'ed rnaterial above the jet plate 24. The lostmotion connections 52 are so proportioned and the parts are so adjustedthat a ram 26 or 26a is under the influence of its operating pair ofeccentrics 47 or 47a for only a relatively small fraction e. g. onesixth, of the cycle of operation, the rams being free to move in adownwards direction under the action of the springs 62 for the remainderof the time. 'It is readily seen that for a major portion of the cycleof operation both rams 26 and 26a are pressing against the powderedmaterial above the plate 24 while for two spaced minor portions of thecycle this material is under the pressure of only one of the rams.

The orifice-s 23 in the jet plate 24 are preferably arranged instaggered relationship in two spaced rows, the rows being, for example,.050 or .070 inch apart, each row being directly under a working face32, 32a. However, since the rams 26, 26a are side by side, the pressureof any one ram, transmitted through the powdered material, urges thematerial over both rows of orifices 23 in a downward direction.

The quantity of fresh material entering beneath a working face 32, 32adepends upon the space created between said face in its uppermostposition and the upper surface of the layer of material over the plate24. If the material should enter beneath the face 32 or 32a at a greaterrate than that at which it was being drawn away from below the plate 24in the form of filaments, the thickness of this layer of material wouldincrease, the clearance created beneath the face 32 or 32a woulddecrease, and the rate of supply of fresh material would correspondinglydiminish. Consequently, in the operation of the apparatus there is abalance between the rate of withdrawal in the form of filaments and therate of supply of fresh powdered material to the upper surface of theplate 24. V

" It is desirable to maintain the material in the chamber 17 undersub-atmospheric pressure. To this end, said chamber is fitted with avacuum line 76 connected to a suitable vacuum pump (not shown), theopening 77 of the vacuum line being shielded by a baffle plate 78 sothat the thermoplastic material will not be drawn into said line. Asecond vacuum line 79 is provided in the upper portion of the hopper 12to enable the pressure in said hopper to be reduced quickly,particularly when starting up the apparatus. To aid in maintaining thesub-atmospheric pressure in the chamber 17 there is provided in thegland 57 a seal 80; while the hop-per 12, the walls of said chamber andthe connection between said hopper and said chamber are all madesubstantially air tight, and the hopper is equipped with a removableairtight cover (not shown). In practice, the hopper 12 is filled withthe powdered filament-formingmaterial, the hopper cover is closed, andthe upper vacuum line 79 is connected to a vacuum pump until there is avacuum of 28 inches of mercury in the hopper. Following this, the lowervacuum line 77, which has heretofore been closed by any suitable valve,is connected to the vacuum pump and the tamping mechanism is placed inoperation.

In the practice of this invention, several spinning machines 10 areoperated from a single shaft 46 and means are provided whereby the rams26, 26a of any one machine may be disconnected from said shaft withoutinterfering with the rotation of the latter. To this end, the apparatusincludes a plate 81 supported at one side by a pair of pivot pins 82mounted on the frame 11, said plate having apertures 83, adapted toreceive the tie rods 53, and having projections 84 adapted to engage theunder sides of the flanges 63 of said tie rods when said projections aremoved upwards by the rocking of said plate. The other side of the plate81 is supported on an cecentric cam 86 which is keyed to a shaft 87'journalled at the end of brackets 88 which depend from the L- girder 67of the frame L Rotation of the shaft 87,

by means of a long handle 89 keyed thereto, causes the .cam 86 torotate, thus rocking the plate 81 to lift the tie rods 53 against theaction of the springs 62. When the parts are thus lifted the rotation ofthe drive shaft 4-6, and the resulting reciprocation of the connectingrods 51, has no effect on the tie rods 53, all of the motion of saidconnecting rods being taken up in the lost-motion connections 52.Accordingly, the collars 54 may be unscrewed'from the tie rods 53 andmay be disconnected from the posts 37, 37a by removing the pins 59; thegland 57 may be unscrewed from the cover 58; and the rams 26, 26a may betaken out of the vessel 17 for cleaning or replacement.

In order to prevent undue transfer of heat from the ends of the jetplate 24, insulation 91 is provided at both ends of the chamber 17.Because of the fact that the chamber 17 is suspended, at its center,from the hopper 12, the ends of said chamber are free from any bolts orother connections which would act to carry away the heat. It is alsodesirable to provide insulation (not shown) around the sides of thechamber 17.

It is to be understood that the foregoing detailed description is givenmerely by way of illustration and that many variations may be madetherein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by LettersPatent is:

1. Apparatus for the production of artificial filamentary products'fromparticles of fusible filament-forming material, said apparatuscomprising a chamber for receiving particles of fusible filament-formingmateriaLa heated spinning jet at an opening of said chamber, a pluralityof rams within said chamber, each of said rams having a working facevforapplying mechanical pressure directly against a layer of said particleson said jet to urge said particles toward said spinning jet, and meansfor recipro eating said rams to apply said'mechanical pressurecontinuously, said means being so constructed and arranged that saidrams move alternatively with at least one ram exerting a pressureagainst said jet throughout the cycle of operation of said rams and witha plurality of rams exerting simultaneous pressures against said jet fora major portion of said cycle.

2. Apparatus for the production of artificial filamentary products fromparticles of fusible filament-forming material, said apparatuscomprising a chamber for receiv-.

ing particles of fusible filament-forming material, a heated spinningjet at an opening of said chamber, said spinning jet having a spinningorifice, a plurality of parallel rams within said chamber, each of saidrams having a working face forapplying mechanical pressure directlyagainst a layer. of said particles on said jet to urge said particlestoward said orifice, and means for reciprocating said rams to apply saidmechanical pressure, said means being constructed and arranged to movesaid r-ams alternately.

3. Apparatus for the production of artificial filamentary products fromparticles of fusible filament-forming material, said apparatuscomprising a chamber for receiving particles of fusible filament-formingmaterial, a jet plate at an elongated opening of said chamber, means forfusing said filament-forming material in passing toward said jet plate,a plurality of elongated rams extending the length of said opening, saidrams being within said chamber and having working faces acting directlyagainst a layer of said particles on said jet plate, and means forreciprocating said rams to apply mechanical pressure continuously to theparticles of material adjacent to said jet plate, said means being soconstructed and arranged that said rams move alternately with at leastone ram exerting a pressure against said jet throughout the cycle ofoperation of said rains and with a plurality of rams exertingsimultaneous pressures against said jet for a major portion of saidcycle.

4. Apparatus for the production of artificial filamentary products fromparticles of fusible filament-forming rams being within said chamber andhaving working faces acting against said jet, and means forreciprocating said rams-to apply mechanical pressure directly to theparticles of material adjacent to said jet and so that said flat sidesmove relative to each other.

5. Apparatus for the production of artificial filamentary products fromparticles of fusible filament-forming material, comprising an elongatedchamber for receiving particles of fusible filament-forming material, anelongated heated spinning jet at an elongated opening of said chamber, apair of elongated rams within said chamber, each of said rams having aworking face extending substantially the length of said opening andacting against said jet, said rams having elongated fiat sides and beingarranged with said flat sides in contact with each other so that theworking face of one ram extends over only a portion of the width of saidopening and the working face of the other ram extends over anotherportion of said width, and means for reciprocating said rams to applymechanical pressure directly to adjoining areas of the particles ofmaterial adjacent to said jet, said means being constructed and arrangedto move said rams alternately. I

6. Apparatus as set forth in claim in which the means for reciprocatingthe rams includes a plurality of posts connected "to said rams, all ofsaid posts being ar-' ranged in one plane.

7. Apparatus for the production of artificial filamentary products fromparticles of fusible filament-forming material, said apparatuscomprising a chamber for receiving particles of fusible filament-formingmaterial, a heated spinning jet at an opening of said chamber, a ramwithin said chamber and having a working face acting against said jet,means for reciprocating said rain to apply mechanical pressure directlyto the particles of material adjacent to said jet, said means includingresilient means urging said ram towards said jet, reciprocating means, alost-motion connection between said resilient means and saidreciprocating means, and additional means for urging a portion of saidlost-motion connection in a direction to hold said resilient meansinoperative.

8. Apparatus for the production of artificial filamentaryproducts fromparticles of fusible filament-forming material, comprising an elongatedtapered chamber for receiving particles of fusible filament-formingmaterial, an elongated heated spinning jet at an elongated opening ofsaid. chamber, said chamber being tapered to said spinning jet, a pairof elongated tapered rams centrally located within said chamber, each ofsaid rams, said rams being tapered in the same direction as said chamberand having a working face extending substantially the length of saidopening and acting against said jet, said rams having elongated flatsides and being arranged with said flat sides in contact with each otherso that the working face of one ram extends over only a portion of thewidth of said opening and the working face of the other ram extends overanother portion of said width, and means for reciprocating said rams toapply mechanical pressure directly and continuously to the particles ofmaterial adjacent to said jet, said means being constructed and arrangedto move said rams alternately, said means includ inga plurality of postsconnected to said rams, all of said posts being arranged in one plane,said means also ineluding spring means urging said rams toward said jet,reciprocating means and a lost-motion connection between said springmeans and said reciprocating means,

the construction and arrangement being such that said rams movealternately with at least one ram exerting a pressure against said jetthroughout the cycle of operation of said rams and with both ramsexerting simultane- .ous pressures against said jet for a major portionof said cycle. l

'9,"A pparatus for the production of artificial filamentary'productsfrom particles of'fusible filament-forming material, said apparatuscomprising an elongated chamsaid'chambeneach of said rams having aworking face extending substantially the length of said opening andacting against saidjet; said rams having elongated 'flat sides'and beingarranged with said flat sides in contact with each other so that theworking face of the ram extends over only a portion of the width of saidopening andtheworking face of the other ram extends over another portionof said width, and means for reciprocating said rams to apply mechanicalpressure directly and continuously to the particles of material adjacentto said jet, said means being constructed and arranged to move said ramsalternately, said means including a plurality of posts connected to saidrams, all of said posts being arranged in one plane, said means alsoincluding spring means urging said rams toward said jet, reciprocatingmeans and a lost-motion connection between said spring means and saidreciprocating means, the construction and arrangement being such thatsaid rams move alternately with at least one ram exerting a pressureagainst said jet throughout the cycle of operation of said rams and withboth rams exerting simultaneous pressures against said jet for a majorportion of said cycle, said jet having a plurality of orifices each ofwhich is countersunk on-the side of the jet toward said ram.

10. A process for the production of artificial filamentary products fromcomminuted fusible filament-forming materials, said process comprisingapplying a continuous mechanical pressure directly to the particles ofmaterials on one side of a layer of filament-forming material in contactwith a heated jet having a spinning orifice therein so as to urge saidparticles towards said orifice whereby said particles are fused by heatsupplied from said jet, said continuous mechanical pressure beingapplied toward said orifice intermittently to different areas of saidlayer, continually supplying fresh powdered material to said areasbetween successive applications of said pressure thereto andcontinuously drawing away the fused material through said orifice in theform of filaments.

11. Apparatus as set forthin claim 3 in which said rams are parallel toeach other within said chamber.

12. Apparatus as set forth in claim 2 in which said working faces applysaid mechanical pressure directly to adjoining areas of said particles.

13. Apparatus as set forth in claim 1 in which said chamber is taperedinwardly toward the jet and the rams are tapered in the same directionas the chamber, the outer sides of the rams at those ends of the ramswhich are closest to said working faces being spaced from the adjacentwalls of said tapered chamber, the construction and arrangement beingsuch that, when a ram is moved away from said jet, particles of saidmaterial pass around that ram in the space between the outer sides ofthe ram and the walls of the chamber and into said layer.

14. Apparatus as set forth in claim 13 in which said rams are paralleland the inner sides of the rams at those ends of the rains which areclosest to said working faces are in contact with one another.

15. Apparatus as set forthin claim 11, the outer sides of 'the rams atthose ends of the rams which are closest to said working faces beingspaced from the adjacent walls of said chamber, the construction andarrangement being such that, when a ramis moved away from said jet,particles of said material pass around that ram in the space between theouter sides of the ram and the walls of the chamber and into said layer.

16. Apparatus as set forth in claim 2, the outer sides of said rams atthose ends of the rams which are closest to said working faces beingspaced from the adjacent walls of said chamber, the construction andarrangement being such that, when a ram is moved away from jet,particles of said material pass around that ram in the space between theouter sides of the ram and the walls 'of the chamber and into said"layer.

17. Apparatus as set forth in claim 16 in which said 'walls are "taperedinwardly toward said jet and the inner sides of the rams at those endsof the rams which are closest to said working faces are in contactwithione particles.

References Cited in the file of this patent UNITED STATES PATENTS McHench e Apr. 4, Billman Feb. 8, Weibel Feb.'13, Upton Nov. 3, Upton Nov. 3,Wienand Dec. 14, Lipscomb et a1 Apr. 10,

